Star Micronics SP500 Series - Drive circuit

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APPENDIX
Drive circuit
The recommended drive unit is shown below.
Notes
• Peripheral Units 1 and 2 cannot be driven simultaneously.
• For continuous driving, do not use drive duty greater than 20%.
• The status of the compulsion switch can be known from the following.
Star mode : The status of the compulsion switch can be known by using
the automatic status function or <ENQ> commands. In the
case of ENQ status, bit 7 will be “1”when pin No. 6 of the
peripheral unit drive circuit is high (switch on).
ESC/POS mode : The status of the compulsion switch can be known by using
the automatic status function, <DLE><EOT>n, and
<ESC>“u”n commands.
• Minimum resistance for coils L1 and L2 is 24Ω.
• Absolute maximum ratings for diodes D1 and D2 (Ta = 25°C) are:
Average Rectified Current Io = 1A
• Absolute maximum rating for transistors TR1 and TR2 (Ta = 25°C) are:
Collector current Ic = 2A
Collector loss Pc = 1.2W
7824
F.G
TR1
M-GND
TR2
M-GND
TR3
+5V
+24V
R1
R2
6
5
4
3
2
1
L1
L2
R3
4.7kΩ
1/4W
Frame
ground
Printer side User side
D1
D2
Peripheral
unit 1
With shield
Peripheral
unit 2
Compulsion
switch